I experimented mirroring and replication. but didn't like active directory requirements very much. first of all configuration is complex. error messages about failover clustering are not explanatory. also as I backup active directory server itself, I would need 4 servers. 2 of them only for AD. it seems waste of resources to me. After 2 weeks of install and test process, active directory is not what I'm looking for.

I want to think like that : "something happened to server, no problem. other server is running and I can easily restore backup image or re-install without configuration headaches". let me give an example. at the moment I use virtual machine in vmserver. if something goes wrong I restore backup, copy vmware files from backup and I'm completely SURE that no configuration problems would occur after restore and in 5 minutes I will be up and running. except SQL. I need a hot backup of sql server and it definitely must be another physical server.

I experimented mirroring and replication. but didn't like active directory requirements very much. first of all configuration is complex. error messages about failover clustering are not explanatory.

Mirroring, replication and failover cluster are entirely different concepts. If you were experimenting with just mirroring or replication you would not be getting any clustering errors, as these technologies are independant of clustering (although they can be incorporated with clustering to an extent).

If you are reviewing SQL Server 2012 I would suggest researching AlwaysOn. It is pretty much the next version of mirroring and works with groups of databases versus individual databases which is what database mirroring does. Also from what I hear it is easier to setup as well. Additionally as of SQL Server 2012 database mirroring is now a deprecated feature in favor of AlwaysOn.

Just for the record, we're in a SQL 2008 forum but we're talking about SQL 2012.

AlwaysOn requires an Active Directory (AD) domain. If you want to avoid AD and Windows Clusters (also required for AlwaysOn) then look into log shipping (or mirroring if you do not mind that it has been deprecated). Personally I would not look at replication for disaster recovery.

If you "need sql server up and running nomatter what happens" then AD and Windows Clustering are in your future, use AlwaysOn.

__________________________________________________________________________________________________There are no special teachers of virtue, because virtue is taught by the whole community. --Plato

AD isn't that big a deal, and most of these technologies will require some parts of it since you are trying to move information around. For a relatively low volume of authentication, I'd think making your machines DCs would work. However you'd have to learn something about networking, and security, otherwise you are asking for trouble at some point.

I agree with what OPC.Three said. Replication is not a good answer unless you are very experienced with how it works and the potential issues.

aykut canturk (1/15/2013)okay, not related with this topic but if I use ms azure for hosting instead of renting my own physical one, would I guarantee that my sql data will always be there ?

Always and forever? I doubt anyone could say for sure how long the Azure platform will remain viable. If the effort failed, which I do not think it will, I suppose Microsoft could evict all Azure tenants but given how much they have invested and the ill-will it would generate I doubt that would occur anytime soon, minimum 5 years, more likely 10+.

In terms of availability itself one of the underlying principles of the cloud platform is that all data is made to be redundant. Data protection is baked right into the Azure SQL Database product. In fact all data sent or changed in the database is automatically committed in two places before the transaction is considered completed and control is returned to the caller and Microsoft guarantees effectively 100% availability of the service.

There are two Azure forums here on SSC. If you have more questions you could consider posting a new thread there.